被动语态变主动语态
spanish is spoken in south America(people)
the homework must be finishhed(the students）
All the new worlds mustbe looked up in a dictionary(we)
has john's room been cleanedalready?(john's sister)
a big cake was given to linda by her friendfor her birthday
this song is often sung now(many children)
we are being taught how to use the newmachine (the worker)